John Barnes, an El Cajon school teacher, can mark milestones with beloved books and book stores.

Working in a library as a kid, and in a bookstore while getting through college. Meeting his grandfather for coffee in the neighborhood bookstore. Getting insights into his Mom by reading the notes she scribbled in the books she’d had as a kid, and had passed down to him.

On Friday, at 2:45 p.m., Barnes was marking a milestone of a different kind - he was Number 93 in a long and winding line at the Borders bookstore in Mission Valley, one of the 399 Borders stores nationwide to begin the painful and final process of bankruptcy liquidation.

“I am sad to see it go, I came to shop here a couple of times a month,” said Barnes, who had 10 hardback books, discounted 20 percent to 30 percent for the liquidation sale, stacked in his arms. “You could meet people here, get recommendations on books to buy, and buy books you never thought to buy. I like to hold books, look at them, turn the pages.

“I’m going to be the last person (on earth) to get an e-book,” said Barnes, smiling wryly. “Just on principle.”

After 40 years in business, Borders Group, the Ann Arbor, Michigan-based bookstore chain, on Friday began liquidating all of its stores, while negotiating a last-minute bid by Alabama-based Books-A-Million for about 30 Borders stores. That bid reportedly includes the 25,000-square-foot Mission Valley store. Another Borders in National City, the only other one remaining in San Diego County, is also liquidating.

The bookstore behemoth, which at its peak boosted over 1,000 locations and annual sales of $4 billion, has seen its business fizzle in recent years as customers switched to e-readers and online retailers like Amazon. The company plans to closes its stores, which employ about 10,700, in phases by September.

Neither Borders or Books-A-Million returned telephone calls. The potential Books-A-Million deal for the 30 Borders stores has yet to be approved by a committee of creditors or the bankruptcy judge.

Bibliophiles weren't the only ones mourning Borders' demise Friday. There will be plenty of unhappy retailers and landlords in strip malls, shopping centers and stand-alone sites around the country, as the Borders’ closures increase available U.S. retail space by as much as 6.3 million square feet, according to real estate experts.

And that’s on top of about 225 stores the book chain began closing after its initial February bankruptcy filing.

With some 12.1 billion square feet of retail space in the U.S., the empty space that Borders brings to the mix seems paltry. But for the retail centers that get saddled with an empty Borders, the impact is “significant,” said Chris Macke, senior real estate strategist for CoStar Group, a Washington, D.C.-based property data company.

On average, the retail centers that had a Borders before the first round of closures had an average vacancy rate of 4.2 percent, which almost doubled to 9.3 percent when the initial 225 stores were closed. If all the remaining 399 stores are shuttered, vacancies at retail centers with a Borders may rise as high as 18.8 percent, said Macke.

Macke said some of the vacant Borders will be hard to fill because of their size. And subdividing can be difficulty because the spaces are often “narrow and deep,” he said.

“You end up with something that resembles a bowling alley,” said Macke.

George Whalin, a Carlsbad retail expert, predicts that the Mission Valley and National City Borders stores should have few problems finding new tenants since both are in desirable locations where retail sales are good.

He noted that the vacant Borders in The Forum Shops near Carlsbad was subdivided and quickly found tenants - apparel stores H&M and Urban Outfitters. That Borders store, as well as Borders stores at Carmel Mountain Ranch, El Cajon’s Parkway Plaza and downtown’s Gaslamp Quarter, closed earlier this year.

“Both the Mission Valley and National City stores are of a size that is fairly desirable and the right sort of store will do well,” said Whalin, founder of Retail Management Consultants.